perfmon: fix perfmon start type argument

When trying to start perfmon with a bundle that has a unique type while
specifying that type as argument, the command fails
(e.g. perfmon start bundle branch-mispred type node).
This error occurs because the returned value of
unformat_perfmon_active_type is actually a perfmon_bundle_type_t, but
it was treated as a perfmon_bundle_type_flag_t by a test in the CLI
function.

However, this test is useless and thus can just be removed.

Type: fix
Signed-off-by: Maxime Peim <mpeim@cisco.com>
Change-Id: I5d8b9815871621e8ee7b935586f4cedbc0e7a53d